What Zone 2 means

Zone 2 comes from training plans that split effort into five heart-rate zones. It is the second-easiest: a steady pace where you breathe more deeply than at rest and can still talk in full sentences. A brisk walk uphill, an easy bike ride or a relaxed swim can all count, depending on your fitness.

Public health guidelines use the term moderate-intensity activity instead. ¹ Zone 2, as most plans describe it, is a steady slice of that moderate range: easy enough to repeat often, firm enough to ask something of your heart and lungs.

You will hear a lot of strong claims about Zone 2 online. The calm version is simpler. Regular aerobic activity is one of the best-supported habits for long-term health, and an easy pace makes it much more likely that you will keep doing it.

How much is enough

The World Health Organization advises adults, including adults over 65, to do 150–300 minutes of moderate-intensity aerobic activity a week, or 75–150 minutes of vigorous activity, or an equivalent mix of the two. ¹ The same guidelines say that some activity is better than none, and that doing more brings further health benefits. ¹

For most people, that means three to five sessions of 30 to 60 minutes. You do not need to reach the top of the range in your first month. Every session adds to your total, and consistency over months matters more than any single workout.

Why fitness is linked to a longer life

In a study of 122,007 adults who did a treadmill test at the Cleveland Clinic, higher cardiorespiratory fitness was associated with lower mortality over a median follow-up of 8.4 years. ² After adjusting for other factors, the least fit group had about five times the risk of dying of the fittest group, and the researchers observed no upper limit to the benefit. ²

In that study, low fitness carried a risk comparable to, or larger than, familiar risk factors such as smoking. ²

This is observational research, and fitter people may differ in other ways. It still points in a clear direction, and steady aerobic work is a gentle way to build fitness. Our VO2max estimator gives you a rough starting number, so you can see where you begin.

How to find your range

The simplest guide needs no device. In a study of the talk test, the point where speaking first became difficult lined up almost exactly with the ventilatory threshold, a common marker of the top of steady aerobic effort. ³ When speech was no longer comfortable, effort was consistently above that threshold. ³ If you can talk comfortably, you are in the right place. If speaking feels hard, ease off.

If you like numbers, our tool Find your Zone 2 uses heart-rate reserve: the gap between your resting and maximum heart rate, a method that goes back to a 1957 study by Karvonen and colleagues. ⁴ When you do not know your maximum, the tool estimates it as 208 minus 0.7 times your age. ⁵ It then shows 60–70% of your heart-rate reserve as your easy range.

Treat any number as an estimate. Your heart rate on a given day can differ from what a formula predicts, so let the talk test have the final word.

How to start

Choose an activity you enjoy enough to repeat. That matters more than which machine or sport you pick.

• Walk briskly, cycle, row, swim or use a cross-trainer.
• Start with a session that feels easy and add a little time each week.
• Keep the whole session conversational. Slow down on hills and in the heat.
• If you also train hard, place easy sessions on the days after your toughest workouts.

Stay safe

Stop and get medical advice if you feel chest pain, dizziness or unusual breathlessness. If you have a heart condition, or have been inactive for a long time, talk to your doctor before you start.

Beta-blockers and some other medicines lower your heart rate, which makes heart-rate zones unreliable. Use the talk test instead.

The WHO guidelines include specific advice for pregnancy and the months after birth. ¹ If that applies to you, check your plan with your midwife or doctor.

Questions people ask